Finally Understand FA focus assist!

I always used the 2X enlargement for my MF assist. This works pretty well in daylight, but when the noise goes up in the EVF/Screen this works less and less well. Samsung does not explain this feature well so I decide to try to figure out FA focus assist myself. I finally figured out how it worked and wanted to share for those who didn't and use manual focus a lot either with NX or adapted lenses.

1. The green bar is measured contrast - This part was pretty obvious.

2. The epiphany was that the red line is PEAK contrast. The reason why this is confusing is because it regularly re-samples this line and so if you move the camera starts to resample. If the camera can't figure out the contrast, it will leave the last number, but sometimes this causes it to look like it in focus but it isn't. If the red line disappears, then you need to re figure out your focus zone. If the green bar is fluctuating, but the red bar is static, then you know you have a max contrast number and can try to "hit" that focus again.

3. Display the grid lines, this will give you a reference point for peak focus. With a high contrast area, I can get to the 1st line of a 1/3 divided screen.

4. The contrast focus calculation zone is in the middle. Notice how the focus zone narrows? This is the area that the bar is measuring. If you don't have have a high contrast area, hopefully you can find some high contrast areas equidistant to your zone of focus.

Basically mimic what a Contrast focus in your camera does, and this system starts to make sense. Scan through your focus zone, then when ever the red line jumps, narrow your focus to reach that peak zone. This is basically center zone focus peaking. I have only tested this at the house with low light with the kit lens, but this should work well with manual lenses.

first, by FA you mean full autofocus? and what body is this for?

I think it stands for focus assistance. You can select that as an option instead of the 2x magnification in the NX camera options. It consists of a vertical green bar in the bottom right corner of the screen that indicates how much contrast the camera measures in the central area of the sensor, plus a red line that shows the peak contrast, a bit like digital VU meters on audio equipment.

I find it pretty intuitive. Wish you could combine it with the magnification.

Random picture found on the web:

I have a feeling that not all NX models have this option (Is it NX10 that doesn't)

On the NX100 you can switch it on from Menu(2) - Set MF Assist to "FA"

Great info! Will try later with my Minolta 50mm 1.7 and see if I can get better focus with it.
--
Rene-Valladares

Does this feature work with adapted lenses or only native NX lenses?
Is this available with the NX11?
--
Steve Nunez~New York City
http://www.stevenunez.com
Oly EPL1, Pan GX1, Samsung NX11, Pentax Q...

It works on all lenses. But as mentioned elsewhere - it's an either/or situation. You can't have both Focus Assoist AND 2x magnification at the same time.

SteveNunez wrote:

Does this feature work with adapted lenses or only native NX lenses?
Is this available with the NX11?
--
Steve Nunez~New York City
http://www.stevenunez.com
Oly EPL1, Pan GX1, Samsung NX11, Pentax Q...

God I wish we could have both, that would be splendid! I found it works better if you want the whole area in the selection box sharp, it has a harder time if you have DOF, 2X multiply is better for macros and intentional blurring. Also you have an easier time if you can find a hard contrast area like (ideally black on white text), but i guess that is no different than AF.

It took me until this thread to discover this difference between NX10 (without this FA feature) and NX11 (with FA feature).

Thomas

I'm curious about this as well pertaining to the NX11!
--
Steve Nunez~New York City
http://www.stevenunez.com
Oly EPL1, Pan GX1, Samsung NX11, Pentax Q...

http://forums.dpreview.com/forums/readflat.asp?forum=1001&message=39057846&changemode=1

this states the nx11 has it but the nx10 does not. Not sure if the firmware has changed this any.

you can find it on the nx100 in camera settings menu

this is what i found in a video, it never really explained the red bar nor anything past "higher green bar is better!"

http://www.youtube.com/watch?v=GTtwqKukVZU&feature=player_detailpage#t=115s